Xp wont load / now no signal

hey ... can anyone help me?
my boyfriend and i both have ibm netvistas.. recently i started having a problem with mine .... the bedreaded ..... xp wont load and monitor goes into sleep mode......
i would unplug it from the wall for a few then it would maybe work.... the other day i had it so i did a system restore .. back a couple months .. now it seems to be ok ... and then it happened...... yesterday my boyfriends pc ..... was on all day it was hot as hell in the house ... i touched the mouse and the pc was on but it froze up immediately.... so we rebooted it then it came on and would freeze at the desktop... and the monitor kept blinking to black screen.. so we rebooted it i went into safe mode .. did a system restore ....... and didnt change anything actually well made it worse cause now we just have a blue screen .... LOL... so i told Him its burning up unplug it ... now it wont come back we get NO SIGNAL ....and when i boot it up only the top light comes on and the bottom light ... does something for like one sec then no activity..... i dont know where to begin .. any ideas and please dont beat me up im trying my best to figure out what the problem is and where to start

If the monitor displays No Signal after powering on the system, then the cable is disconnected, or the computer is not even posting. Since you mentioned the heat, I would think that the system fatally overheated. If the lights come on, your power supply is probably OK, but your motherboard, CPU, or both are toast. Since it is a brand name system, a replacement motherboard will probably be proprietary, which means $$$. If the system is a few years old, this would be a good time to upgrade.